Can I apply for a 3-month retirement visa in Thailand every year?

You can, but seems utterly pointless for 90 days. You can spend 90 days without any visa,

@Richard *******

what is your true intention?

*** do you want to enjoy a holiday of longer than 90 days? Then get the multi entry Tourist visa. This visa can get you up to almost 9 months in Thailand

*** do you want a holiday longer than 90 days? Then get the 90-days single entry Non-Imm-O visa in your home country, enter Thailand, exit before the 90 days are over, enter visa-exempt and get stamped in for 60 days and extend for 30 days - 90+60+30 = 180 days

*** you could enter visa-exempt, get stamped in for 60 days, apply for the “change of visa type” to the 90-days Non-imm-O visa. But never go for the extension, exit Thailand before the 90 days stay permit expires. Re-entry and try that game, again. I think your Immigration officer was right – you can’t apply for the “change of visa type” in a consecutive manner. You got one shot in a calendar year . . . . .so the correct answer is: You can do the "change" every calendar year, again and again . . .did you read the requirements for this? You need a 3- 6-months rental contract, and you need 800.000 THB sitting in your Thai bank account. In case you ever had an overstay, you cannot apply for the "change"

Why do you want a retirement visa? You could do 3 months a year on a tourist visa and you won’t need to keep 0 in a bank account or provide evidence of 65,000 per month income + the visa process fee. Depending on the country you live in a tourist visa is free.

Just get your retirement visa extension, check in every three months at immigration and renew once a year 1900 baht.

There is no point just come in on visa exempt 60 days plus one extension at immigration of 30 days

Anytime you want. Even multipe times a year. Meet the requirements and go for it.

If you meet all the requirements... Why not !!

Should be, as long as you meet the requirements each year.